CN204269739U - Lightning strike diagnosis and real-time alarm device based on line arrester - Google Patents

Abstract

The utility model provides thunderbolt diagnosis based on leakage conductor and real time warning device, comprise: for measuring the data acquisition module of discharge current, be connected with data acquisition module and for obtain discharge current amplitude, direction and spectrum information signal processing module, the reason causing leakage conductor action is judged according to the amplitude of discharge current, direction and spectrum information, and identifying and store the thunderbolt identification module of thunder and lightning polarity, thunderbolt type, leakage conductor actuation time and number of times, this thunderbolt identification module is connected with described signal processing module; Also comprise and be connected with described data acquisition module, signal processing module, thunderbolt identification module respectively and the supply module of working power is provided.Can actuation time of record circuit lightning arrester, action reason and number of times, can contrast to carry out thunderbolt event analysis with concrete thunderbolt event, by discharge current waveform parameter during leakage conductor action, leakage conductor action reason, thunderbolt type are identified.

Description

Lightning strike diagnosis and real-time alarm device based on line arrester

technical field

The utility model relates to the technical field of lightning protection, in particular to a lightning strike diagnosis and real-time alarm device based on a line lightning arrester.

Background technique

Compared with other lightning protection measures, installing line arresters on transmission lines, especially in areas with strong lightning activities or high soil resistivity and difficulty in reducing grounding resistance, can effectively reduce the tripping accident rate and improve the lightning resistance level of transmission line towers. Therefore, the installation and use of line arresters can achieve better lightning protection effects and greatly improve the operational reliability of the power grid.

The line arrester widely adopts the out-of-band series gap structure. Since the arrester body and the conductor are separated by a gap, the line arrester does not bear the action of the line operating voltage during normal operation of the system. Therefore, there is no aging problem in the resistive sheet of the arrester. Even if the arrester body fails, due to the isolation effect of the gap, it will not cause a short circuit and cause the line to trip.

Although the operating performance and lightning protection effect of the existing line arrester are good, the monitoring technology of the line arrester and its role in the line lightning protection work still need to be improved, which is mainly reflected in the following aspects:

(1) The line arrester only has the function of recording the number of actions, and cannot record the action time, which cannot be compared with the specific lightning strike event, and cannot be used for lightning strike event analysis.

(2) The line arrester does not record the discharge current parameters, and cannot know the current magnitude and spectrum information during the operation, and cannot compare and analyze it with the lightning information of the lightning positioning system. deviation.

(3) When the arrester operates, it is often a thunderstorm and a lightning strike fault occurs on a nearby line. The action information cannot be transmitted to the relevant operating personnel in time, which is not conducive to the rapid implementation of the line special inspection task, and the timeliness of the lightning hidden danger investigation is difficult to guarantee.

(4) The search for lightning strike fault points is relatively complicated. Existing lightning arresters do not judge the type of lightning strike, and cannot record and count the weakness of lightning protection performance of towers in the nearby area, which is not conducive to the development of lightning strike risk assessment for line-related sections.

Based on the above situation, it is necessary to develop a lightning fault diagnosis and real-time alarm device based on the existing line arrester, which can record the waveform parameters of the leakage current, judge the type of lightning fault, and send prompt information to the operation and maintenance personnel in time. No such device exists yet.

Contents of the invention

The purpose of this utility model is to propose a lightning strike diagnosis and real-time alarm device based on the line arrester, to identify the cause of the action of the line arrester and the type of lightning strike according to the characteristics of the measured operating current, and send prompt information to the operator.

In order to solve the problems of the technologies described above, the technical scheme of the utility model is as follows:

The lightning strike diagnosis and real-time alarm device based on the line arrester is installed on the pole tower where the line arrester is installed, including: a data acquisition module for measuring the leakage current that causes the action of the line arrester, connected to the data acquisition module and said leakage current A signal processing module that performs analog-to-digital conversion to obtain the amplitude, direction, and spectrum information of the leakage current, judges the cause of the action of the line arrester based on the amplitude, direction, and spectrum information of the leakage current, and triggers the line arrester when the lightning strikes. A lightning strike recognition module that identifies and stores lightning polarity, lightning strike type, line arrester action time and times during action, and the lightning strike recognition module is connected to the signal processing module; A power supply module that is connected to the identification module and provides working power.

The data acquisition module includes feed-through current transformers respectively arranged on the tower body and the protection valve of the line arrester, and the output end of the feed-through current transformer is provided with a preprocessing circuit for outputting proportional voltage waveform signals, The preprocessing circuit is composed of shaping, limiting and filtering circuits electrically connected in sequence.

The signal processing module includes a frequency spectrum calculation unit for calculating the current frequency component distribution according to the waveform of the proportional voltage waveform signal, and an amplitude direction analysis unit for identifying the magnitude and direction of the proportional voltage waveform signal .

The lightning strike identification module includes an action cause judgment unit for analyzing the frequency component and outputting a high level when the lightning strike triggers the action of the line arrester, and is used for determining the cause of the action according to the amplitude of the proportional voltage waveform signal when the high level is received. The lightning strike type judging unit that outputs the lightning polarity and lightning strike type in the direction and direction, and the lightning strike action counting unit for storing the lightning polarity, lightning strike type, and action time and times of the line arrester, the action cause judgment unit, and the lightning strike type judgment unit The unit and the lightning strike counting unit are electrically connected in sequence.

The utility model has the advantages of simple and reasonable structure, and can record the action time, action reason and times of the line arrester, so that it can be compared with specific lightning strike events, used for analysis of lightning strike events, and discharge current when the line arrester operates Waveform parameters can identify the reason for the action of the line arrester and the type of lightning strike, so that real-time prompt information can be sent to the operation and maintenance personnel in time, so as to quickly carry out special line inspections, troubleshoot hidden dangers or repair.

Description of drawings

Fig. 1 is a block diagram of the utility model;

Fig. 2 is the structural block diagram of data acquisition module and signal processing module;

Fig. 3 is a schematic diagram of the principle of frequency component calculation criterion in the signal processing module;

Figure 4 is a simulation diagram of the current distribution of lightning shielding;

Figure 5 is a simulation diagram of the current distribution of lightning counterattack;

Fig. 6 is a simulation diagram of the operating current of the line arrester under the operating overvoltage;

Fig. 7 is a logic circuit diagram of a lightning strike type judging unit;

Fig. 8 is a signal flow diagram of a data acquisition module, an information processing module, and a lightning strike recognition module;

Fig. 9 is a structural block diagram of a power supply module;

Explanation of reference signs: 1. Power supply module; 2. Data acquisition module; 3. Signal processing module; 4. Lightning strike recognition module; 5. Information sending module; 6. Line arrester; 7. Tower body; Transformer.

Detailed ways

In order to make the above purpose, features and advantages of the utility model more obvious and understandable, the utility model will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Example

As shown in the figure, the lightning strike diagnosis and real-time alarm device based on the line arrester is set on the tower where the line arrester 6 is installed, including: a data acquisition module 2 for measuring the leakage current that causes the action of the line arrester, and a data acquisition module 2 A signal processing module 3 that is connected and performs analog-to-digital conversion on the leakage current to obtain the amplitude, direction and spectrum information of the leakage current, and judges and triggers the action of the line arrester according to the amplitude, direction and spectrum information of the leakage current The lightning strike recognition module 4 that identifies and stores the lightning polarity, lightning strike type, action time and times of the line arrester when the lightning strike triggers the action of the line arrester, the lightning strike recognition module 4 is connected to the signal processing module 3; A power supply module 1 that is connected to the data collection module 2, the signal processing module 3, and the lightning strike recognition module 4 and provides working power.

The lightning strike diagnosis and real-time alarm device of the utility model is arranged on the pole tower, and is connected with the line arrester 6. By adding functional modules to some structures of the line arrester 6, it has the functions of lightning strike recognition and alarm.

In this embodiment, the frame of the entire device is shown in FIG. 1 . The main components include a power supply module 1, a data acquisition module 2, a signal processing module 3, a lightning strike recognition module 4, and an information sending module 5.

1. Data acquisition module

The data acquisition module 2 includes feed-through current transformers 8 respectively arranged on the tower body 7 of the pole tower and the line surge arrester protection valve (ZnO protection valve). The output ends of the two feed-through current transformers 8 are provided with shaping, amplitude limiting , filter circuit, and signal integration circuit, etc., are used for signal preprocessing.

The two through-hole current sensors installed on the tower body 7 and the arrester protection valve are used as the measurement terminals. Since the output voltage is proportional to the current differential, the output voltage needs to be integrated and restored to a voltage signal proportional to the actual measured current. At the same time, processing methods such as shaping, limiting, and filtering are added to output a voltage waveform signal proportional to the operating current, that is, an equal-proportional voltage waveform signal waveform that can be used for subsequent analysis is obtained. By analyzing the voltage waveform, the correlation of the operating current is obtained. information.

2. Signal processing module

The signal processing module 3 includes a spectrum calculation unit and an amplitude direction analysis unit, the spectrum calculation unit is used to calculate the current frequency component distribution according to the waveform of the equal proportion voltage waveform signal, and the amplitude direction analysis unit is used to identify the equal proportion voltage waveform The magnitude and direction of the signal.

One function of the signal processing module 3 is to obtain the amplitude and direction of the lightning current and digitize it. This part is mainly connected by a peak hold, a voltage reference circuit and a voltage comparator in sequence, that is, the amplitude direction analysis unit, which is set in the data acquisition After the integrating circuit of module 2.

Another function of the signal processing module 3 is to utilize the processed proportional voltage waveform signal waveform to calculate its frequency component distribution, according to the set criterion 20lg(Amax/A)≤40, that is, the relative component is 1% of the maximum component. Boundary, get the current main frequency component range f<fm, the principle is shown in Figure 3. This part is the spectrum calculation unit, which is arranged after the integration circuit, and is composed of a spectrum calculation circuit and a frequency component analysis circuit sequentially connected.

3. Lightning strike identification module

The lightning strike identification module 4 includes an action cause judgment unit, a lightning strike type judgment unit, and a lightning strike action counting unit.

a. Action cause judgment unit

Judging from the spectrum point of view whether the measured current is caused by lightning overvoltage leakage; if so, output a high level (R=1), otherwise output a low level (R=0).

The frequency critical value fm is obtained according to the distribution of current frequency components. If fm<15kHz, it is considered that the action of the line arrester 6 is caused by operation overvoltage. If fm>80kHz, it is considered that the action of the line arrester 6 is caused by lightning overvoltage. It can be seen that the process of judging the cause of the action of the line arrester is actually a process of selecting between the two causes of lightning strike overvoltage and misoperation overvoltage, which can be realized based on existing selection circuits in the technical field.

The above operating overvoltage and lightning overvoltage action recognition principles are as follows:

1. The characteristics of the two types of overvoltage

①Operating overvoltage: Several cycles lasting from hundreds of μs to power frequency can be summarized into two typical waveforms: one is to superimpose a high-frequency attenuating oscillatory wave of hundreds to thousands of Hz on the power frequency voltage component; The second is to superimpose a non-periodic shock wave on the power frequency voltage component, the wave front time is 0.1-0.5ms, the half-peak time is about 3-4ms, and the frequency is within a few thousand Hz.

②Lightning overvoltage: the wave front time is in the range of 1-4μs, with an average of about 2.6μs; the wavelength (half-peak time) is in the range of 20-100μs, mostly about 40μs, and the frequency is 10k-100kHz.

2. Verification

Figure 4-6 shows the operating current of the line arrester 6 and the frequency component distribution diagram of the current passing through the tower to the ground obtained from the simulation calculation in the case of lightning overvoltage (shielding and counterattack) and operating overvoltage, as shown in Fig. The middle ordinate is the current value, and the abscissa is time. Fig. 4(a) is the current distribution of the line arrester when the lightning shields, and Fig. 4(b) is the current distribution through the tower when the lightning is shielded. Fig. 5(a ) is the current distribution of the line arrester when the lightning strikes back, Fig. 5(b) is the current distribution through the tower to the ground when the lightning strikes back, and Fig. 6 is the operating current of the line arrester under the operating overvoltage. It can be seen from the above that the action time of the arrester under different circumstances is: lightning strike (<200μs, μs level), operating overvoltage (>2ms, ms level), and the frequency components of lightning current are mainly distributed as follows: lightning shielding (0～120kHz), Lightning counterattack (0~100kHz), operating overvoltage (0~10kHz), consistent with the above.

b. Lightning type judgment unit

Note that the direction of the current measured by the feed-through current transformer 8 arranged on the line arrester 6 is D1, and the direction of the current measured by the feed-through current transformer 8 arranged on the tower body 7 is D2, and D1 and D2 are collectively referred to as D, Wherein the current positive direction of the through-type current transformer 8 on the line lightning arrester 6 is recorded as wire → cross arm, and the current positive direction of the through-type current sensor on the tower body 7 is cross arm → ground surface. If the identification current is in the positive direction, Then let D=1, otherwise D=0. The digital quantities of D1, D2, and EN (connected to the action cause signal R) are respectively used as inputs to the logic circuit shown in Figure 7 to obtain two digital quantities representing the lightning strike type S and lightning polarity T. Among them, the left NOR gate has the enabling function, and the input value of the EN terminal is R, that is, the circuit works only when the action of the arrester is caused by a lightning strike. When the output S=1, it is shielding, and when S=0, it is counterattack; the right side is An XOR gate, when the output T=1, it is a positive polarity mine, and when the output T=0, it is a negative polarity mine.

Judgment principle of lightning polarity and lightning strike type:

1. When shielding strikes, the lightning current comes from the wire. After the line arrester 6 operates, the lightning leakage flows through the line arrester 6 and enters the ground through the tower.

2. When counterattacking, the lightning current comes from the top of the pole tower. After the line arrester 6 operates, part of the lightning discharge flows through the line arrester 6 and enters the wire, and the other part enters the ground through the pole tower.

The lightning polarity, lightning strike type sensor measured current properties and logic judgment truth table are shown in Tables 1 and 2.

Lightning polarity lightning type Arrester current flow direction Tower body 7 current flow direction just siege Conductor → cross arm Cross arm → surface just fight back Cross arm → wire Cross arm → surface burden siege Conductor → cross arm Cross arm → surface burden fight back Cross arm → wire Cross arm → surface

Table 1

Lightning Polarity (T) Lightning Type(S) Arrester current direction (D1) Tower body 7 current direction (D2) 1 1 1 1 1 0 0 1 0 1 0 0 0 0 1 0

Table 2

c. Lightning stroke counting unit

Using a counter with an enabling function, if it is judged that the cause of the action is a lightning strike, that is, R=1, the counter will automatically add 1 to the number of lightning strikes, and at the same time record the lightning strike time and store it in the memory.

Referring to FIG. 9 , the data acquisition module 2 , the signal processing module 3 , and the lightning strike recognition module 4 are connected together according to the above-mentioned signal flow direction.

4. Power supply module

The power supply module 1 includes solar panels and batteries, and can also be powered by inductive energy harvesting when conditions permit; the power consumption part of the device includes various active circuits such as integrating circuits, signal processing circuits, logic circuits, and counters, and is powered by DC power supply. host. The energy source is mainly solar energy. If the wire flows through the alternating current and the insulation coordination meets the requirements, the wire induction energy harvesting can be used as a supplement. The power supply module 1 may adopt a block diagram structure as shown in FIG. 8 .

Preferably, an information sending module can also be set to send lightning strike diagnosis and real-time alarm information to operation and maintenance personnel in time.

5. Information sending module

The information sending module 5 includes a data storage unit connected to the signal processing module 3, and a GPRS/GSM transmitting unit for sending diagnosis and alarm reports to operation and maintenance personnel through GPRS/GSM.

According to the data stored in the storage unit in different processing stages, under the premise that lightning strikes cause the line arrester 6 to act, that is, R=1, integrate the information obtained from the processing and analysis of the above modules and units, including lightning polarity, lightning strike type, Arrester operating time and operating current amplitude, etc., according to the pre-stored contact list, the above information is transmitted long-distance through the GPRS/GSM communication module, and the mobile terminal can be directly connected to the mobile terminal through the GPRS transmission mode or the GSM mode through the SIM card. For communication, the information is sent to the mobile phone of the relevant personnel in the form of a short message. The GPRS/GSM transmitting unit can be built by a single-chip microcomputer, and the AT command is sent and the data is transmitted through the serial port.

The utility model has a simple and reasonable structure, and can record the action time, action reason and times of the line arrester 6, so that it can be compared with a specific lightning strike event, used for analysis of lightning strike events, and the discharge current waveform parameters when the line arrester 6 operates , to identify the reason for the action of the line arrester 6 and the type of lightning strike, and send prompt information to the operation and maintenance personnel in time, so as to quickly carry out special line inspections, troubleshoot hidden dangers or overhaul.

The above detailed description is a specific description of the feasible embodiment of the utility model. This embodiment is not used to limit the patent scope of the utility model. Any equivalent implementation or change that does not deviate from the utility model shall be included in this case within the scope of the patent.

Claims (4)

1. The lightning strike diagnosis and real-time alarm device based on the line arrester is arranged on the pole tower where the line arrester is installed, and is characterized in that it includes: a data acquisition module for measuring the leakage current that causes the action of the line arrester, connected with the data acquisition module and A signal processing module that performs analog-to-digital conversion on the leakage current to obtain the amplitude, direction, and spectrum information of the leakage current, and judges the cause of the action of the line arrester based on the amplitude, direction, and spectrum information of the leakage current, And identify and store lightning polarity, lightning strike type, line arrester action time and number of lightning strike identification modules when the lightning strike triggers the action of the line arrester, the lightning strike identification module is connected with the signal processing module; it also includes the data acquisition module respectively , a signal processing module, and a lightning strike identification module are connected to provide a power supply module for working power. 2. lightning strike diagnosis and real-time alarm device based on line arrester according to claim 1, is characterized in that, described data acquisition module comprises the through-hole current transformer that is respectively arranged on tower body and line arrester protection valve, so The output end of the feedthrough current transformer is provided with a preprocessing circuit for outputting equal-proportional voltage waveform signals, and the preprocessing circuit is composed of shaping, limiting and filtering circuits electrically connected in sequence. 3. The lightning strike diagnosis and real-time alarm device based on the line lightning arrester according to claim 2, characterized in that, the signal processing module includes a spectrum calculation for calculating the current frequency component distribution according to the waveform of the proportional voltage waveform signal unit, and an amplitude direction analysis unit for identifying the amplitude and direction of the proportional voltage waveform signal. 4. The lightning strike diagnosis and real-time alarm device based on the line arrester according to claim 3, wherein the lightning strike recognition module includes a high-level signal for analyzing the frequency component and outputting a high level when the lightning strike causes the line arrester to act. Action reason judging unit for outputting lightning polarity and lightning strike type judging unit according to amplitude and direction of proportional voltage waveform signal when receiving said high level, and for storing said lightning polarity, lightning strike The lightning strike action counting unit for the type, action time and times of the line arrester, the action cause judgment unit, the lightning strike type judgment unit, and the lightning strike action counting unit are electrically connected in sequence.